There is not a way of creating itemGroups through the Merchant Dashboard currently, however it is possible to create an itemGroup (also referred to as "Item with Variants") using the Clover Inventory Application on a Clover device.
To create an itemGroup through the Inventory App, simply open the app on your Clover device and select "Add Item with Variants" and follow the app's flow. (see Inventory Application docs)
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